1. Field of the Invention
The present invention relates to an automobile headlamp system and, more particularly, to improvements in a mechanism for operating a cover for at least one automobile headlamp which can be moved between its retracted position inside the body of the automobile and its protruded position outside the body. The cover can be opened or closed with the movement of the headlamp. When the headlamp is in its retracted position, the cover is in its closed position and forms a part of the outer surface of the body of the automobile.
2. Background Information
In a known cover-operating mechanism for use with a retractable automobile headlamp system as described above, a bracket supporting a headlamp is mounted so that its rear end portion rotates about an axis extending across the vehicle, A lamp cover is securely fixed over the bracket such that the cover and the headlamp rotate about the same axis.
In another known mechanism, a bracket to which a headlamp is mounted is held by a lamp-operating linkage so as to be movable up and down, the linkage having an upper lever and a lower lever. A lamp cover is fixedly mounted to the upper lever and can rotate with the upper lever about the same axis extending across the vehicle.
Referring to FIGS. 4 and 5, there is shown the construction disclosed in Japanese Patent Laid-Open no. 59-192633. This construction includes a headlamp 11, a lamp bracket 12 to which the lamp 11 is mounted, a lamp-operating linkage 18, a stationary bracket 31 fixed to the body of a vehicle, a lamp cover 21, and a rod 51. The linkage 18 consists of an upper lever 13 and a lower lever 14. The lamp bracket 12 is fixed to the stationary bracket 31 by the linkage 18. The cover 21 is pivotally mounted to the body of the vehicle near its rear end 21a. One end of the rod 51 is pivotally mounted to the lower lever 14 of the linkage 18, while the other end is pivotally mounted to the cover 21. As the headlamp 11 is moved upward or downward, the cover 21 is rotated by the rod 51.
In these conventional cover-operating mechanisms of retractable headlamp systems, the lamp cover is pivotally mounted directly to the vehicle body, and the axis of rotation of the cover which runs across the vehicle is fixed.
In an automobile retractable headlamp system it is necessary that the lamp cover does not interfere with the engine hood when the lamp cover is opened or closed and that the hood can be opened and closed without interfering with the lamp cover when the lamp cover is open. Preferably, the parting line between the rear end of the lamp cover and the front end of the engine hood has a good shape. However, limitations are imposed on the shape of the parting line in order that the prior art automobile headlamp system satisfies the aforementioned requirements.
Specifically, if the rear end of the lamp cover is located just above the axis of rotation, then when the lamp cover is opened, the rear end rotates around a hinge and moves backward, thus interfering with the front end of the engine hood. For this reason, the rear end of the engine hood is located above and behind the axis of rotation, for causing the rear end of the hood to fall into the vehicle body when the lamp cover is opened, or the rear end of the hood is located above and ahead of the axis of rotation to elevate the rear end when the lamp cover is opened. Thus, the rear end of the lamp cover is prevented from interfering with the front end of the hood. Therefore, it is impossible to cause the parting line between the rear end and the front end of the engine hood to cross the axis of rotation of the hood. Thus, it is inevitable that the parting line is placed either above and behind or above and ahead of the axis of rotation. The parting line extends straight across the vehicle, which imposes great limitations on the design.
As shown in FIG. 3, if a curved portion 21c having a large radius of curvature is formed around the rear end 21a of the lamp cover 21, then a part of the curved portion 21c is located at 21e just above the axis of rotation 21d of the lamp cover 21. When the lamp cover is opened, this part moves rearward to interfere with the engine hood. Therefore, the axis of rotation 21d must be positioned either behind or in front of the curved portion. If the axis of rotation 21d is located behind the rear end 21a of the lamp cover 21, the cover-operating mechanism itself increases in size and so this arrangement is difficult to achieve. If the axis of rotation 21d is disposed in front of the curved portion 21c, an opening that is large enough to expose the headlamp 11 cannot be formed around the rear end 21b of the lamp cover 21. In this way, this layout is impossible. As a result, it is impossible to form a curved portion of a large radius of curvature around the rear end 21a of the lamp cover 21.